A man rides a motorbike past a billboard depicting Iranian ballistic missiles in service in Tehran. AFP
Iranian airports were closed in Tehran, Shiraz, and Isfahan and flights were cleared of significant areas of Iranian airspace, according to FlightRadar24 which tracks air traffic.
At 0445 GMT, airports and airspace had returned to normal capacity, with closure notices posted on the US Federal Aviation Administration database removed as well.
Still, several airlines completely cancelled flights through or near Iranian airspace.
Emirati Flydubai completely cancelled flights to Iran, after one of its earlier flights had to turn back to Dubai.
German Lufthansa cancelled all flights to Tel Aviv and Erbil until Saturday and also announced plans to avoid Iraqi airspace.
Iranian air defences at an air base and nuclear site near the city of Isfahan fired on drones early Friday, raising fears of a possible Israeli strike in response to Tehran's unprecedented retaliation with drone-and-missile assault on the country last Saturday.
The Israeli army did not respond to a request for comment.
However, speaking at the G7 meeting in Capri, Italy's Foreign Minister Antonio Tajani said the US administration was informed at the "very last minute" by Israel about the attack, and said "there was no involvement" from Washington.
US Secretary of State, Antony Blinken continued to avoid answering questions about the strikes.
However, he repeated that the US was "not involved" in any offensive military operations and is continuing to work for de-escalation.
"All I can say is that for our part and for the entire G7, our focus has been on de-escalation and on avoiding a larger conflict. Actually, that's been true since day one and the horrific events of October 7. A big part of our approach has been to prevent the conflict from spreading to avoid escalation everywhere."
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